Automatic dispenser for hot fluids under pressure

ABSTRACT

A heated dispenser body internally contains a retainer for a tubular actuator that is mounted for pivotal movement about an axis that is parallel to a plane intersecting an adjustable nozzle on the free end of the actuator. The nozzle houses a valve seat that is normally closed by a valve head formed on the forward end of an elongate stem that has an rear end flange biased against a forward end of a hollow spool that is axially slidably mounted in the housing. A biasing means normally maintains the valve head in a closed position on the valve seat. Upon deflection of the nozzle by an article moving in the aforementioned plane, the actuator is rocked about its axis whereby the flange of the actuator cams the spool rearwardly to effect withdrawal of the valve head from its seat to permit a hot liquid under pressure to be expelled from an orifice in the nozzle. The rear end of the body is closed by a flow adjusting plug whose normal clearance relative to the spool can be externally adjusted as desired to positively limit the range of possible axial travel by the spool and, correspondingly, throttle the valve opening to a desired degree. The retainer is formed with a central passage having an annular pocket containing an O-ring, on a back-up ring, in fluid sealing engagement with the actuator. The relationship of the O-ring and the pivot axis of the actuator is such that the median diametral plane of the O-ring is in the plane of the pivot axis.

[451 Dec. 17, 1974 United States Patent [191 Moen [5 AUTOMATIC DISPENSERFOR HOT tersecting an adjustable nozzle on the free end of the FLUIDSUNDER PRESSURE actuator. The nozzle houses a valve seat that is normallyclosed by a valve head formed on the forward [76] Inventor tfgsgi i gg gMichigan end of an elongate stem that has an rear end flange bi- May 4,1973 Appl. No.: 357,501

ased against a forward end of a hollow spool that is ax- [22] Filed:ially slidably mounted in the housing. A biasing means normallymaintains the valve head in a closed position on the valve seat. Upondeflection of the nozzle by an article moving in the aforementionedplane, the actuator is rocked about its axis whereby the flange of theactuator cams the spool rearwardly to effect withdrawal of the valvehead from its seat to permit a hot Int. B67d 5/62 liquid under pressureto be expelled from an orifice in the nozzle. The rear end of the bodyis closed by a flow adjusting plug whose normal clearance relative to003 1 2 06 0 2 6. 32m 10/ ,4l E 0 HUN 1 2 0 2 ,4 00 n0 5 n 6 w 2 2 2 M.n F N 5 the spool can be externally adjusted as desired to positivelylimit the range of possible axial travel by the spool and,correspondingly, throttle the valve opening to a desired degree.

3,198,394 8/1965 Lefer 3,482,737 12/1969 Marder et al...

3,642,173 2/1972 Marraffino.,...........,....... 222/402.24 The taineris formed with a central passage having an annular pocket containing anO-ring, on a back-up Primary ExaminerStanley H. ll rg ring, in fluidsealing engagement with the actuator.

A n y, g Firm-Frederick Mueller The relationship of the O-ring and thepivot axis of the actuator is such that the median diametral plane ofthe O-ring is in the plane of the pivot axis.

[57] ABSTRACT A heated dispenser body internally contains a retainer fora tubular actuator that is mounted for pivotal movement about an axisthat is parallel to a plane inl7 Claims, 8 Drawing Figures AUTOMATICDISPENSER FOR HOT FLUIDS UNDER PRESSURE BACKGROUND OF THE INVENTION Thepresent invention relates generally to dispensers for fluids and, moreparticularly, to automatic dispensers for hot liquids under pressure.The invention appears to have its primary utility as a hot glueapplicator for paper or cardboard box forming machines, e.g., Bliss boxmachines. Accordingly it will be specifically described with respect tothat field, by way of illustration but not limitation.

'The use of hot and cold glue applicators in machines for formingcardboard containers from container blanks is noted in my U.S. Pat. No.3,273,757 of Sept. 20, 1966. The patent discloses a dispenser that isadapted primarily for the application of cold glue and has been highlysuccessful with such material. However, problems have been encounteredin attempts to use the cold glue applicator of the patent to dispensehot glues.

More particularly, hot glues are typically applied at pressures up to500 psig and temperatures up to 420F. The patented dispenser employs atubular actuator barrel having a ball-like rear end that is swivellymounted in a supporting body and biased against an O-ring providing afluid seal between the external surface of the enlarged ball end and anannular shoulder of the body which seats the O-ring. In order toaccommodate the swiveling movement of the actuator barrel, the openingin the body through which the barrel extends is relatively large, ascompared to the cylindrical surface of the barrel, to provide thenecessary clearance. However, when subjected to hot glue under pressureit has been found that in the patented dispenser the O-ring seal veryquickly is extruded through the large clearance space, whereby the sealis lost. Further, due to the high fluid pressures involved, the ballhead of the actuator barrel is so firmly seated against the O-ring thatan excessive actuating pressure from an article to which glue is to beapplied is required at the nozzle end of the barrel.

SUMMARY OF THE INVENTION In a presently preferred embodiment of thisinvention a heated body is provided with a port for the connection of aconduit means in communication with a supply of hot glue under pressure.Internally, the body supports a spool for axial slidable reciprocationbetween positive limits imposed by a flow adjusting plug, closing therear end of the body, and a retainer and actuator assembly, closing theforward end of the body. The hollow spool is provided with an externalcircumferential groove defining an annulus with the inner wall of thebody in fluid communication with the hot glue port. A forward or lowerend wall of the spool is slotted to provide passage means for the hotglue to flow forwardly through an actuator barrel. A retainer in theforward end of the body is formed with a central axial passagetherethrough to receive the actuator barrel. Adjacent its rear or innerend this passage is provided with an annular groove mounting an O-ringon a back-up ring, the former providing a fluid seal between theexternal surface of the actuator barrel and the surrounding wall of thepassage through the retainer. At its innermost end the actuator barrelhas a radially outwardly extending flange that is mounted on a wear ringwhich, in turn, is

pivotally rockable on a diametrically opposite pair of pivot pinssecured to the rear face of the retainer. The pivot pins are positionedto define a pivot axis for the wear ring which is in the same plane asthe median diametral plane of the O-ring for the actuator barrel.

An axially adjustable nozzle is mounted on the free forward end of theactuator barrel and internally mounts a valve seat means around anorifice formed through the nozzle. An elongate valve stem within thebarrel is formed with a valve head at its forward end and, at its rearor innermost end, the stem is normally biased into seating engagementwith the inside of the forward wall of the spool, to effect closing ofthe valve port. Upon an article, such as a container blank, coming intoengagment with the nozzle, the actuator barrel is pivoted about thepivot pins, whereby the flange of the actuator earns the spoolrearwardly relative to the body to thereby withdraw the head of thevalve stem from the seat, thus allowing the hot glue to be expelledthrough the nozzle orifice.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a partial, vertical sectionalview of a presently preferred embodiment of the invention as mounted inoperative position on a box forming machine;

FIG. 2 is an axial sectional view, on a larger scale, of the hot gluedispenser shown in FIG. 1, taken on the line 2--2 of FIG. 1;

FIG. 3 is a view similar to FIG. 2 but with the internal parts showndisplaced out of normal position to a condition in which the valve ofthe device is open;

FIG. 4 is a transverse cross sectional view, taken on the line 4-4 ofFIG. 2, to illustrate the pivot pins for the actuator assembly;

FIG. 5 is a perspective view of the spool;

FIG. 6 is a lower end elevational view of the spool of FIG. 5; I

FIG. 7 is a transverse cross sectional view taken on the line 7-7 ofFIG. 2;

FIG. 8 is a perspective view of an O-ring back-up member, with a portionthereof being cut away to better illustrate the radial cross sectionalconfiguration thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, a boxforming machine'is generally indicated by the numeral 10, illustratingone field of use of the dispenser of this invention. Typically, such amachine includes a framework made up of a plurality of cross members 11,side member 12, and columnar members or legs 13 to provide a rigidsupport for a parallel pair of angle-iron box blank guide members 14. Onboth sides of the machine 10 one or more upstanding brackets 15 arerigidly secured thereto to support one or more hot glue dispensers in afixedly adjusted position to apply a stripe of glue to a margin or flapof each of a series of box blanks fed along the guide members 14. In theillustrated case, the presently preferred embodiment of hot gluedispenser is indicated generally by the numeral l8 and, by way ofillustration, is held in place within a mounting ring 19 by a screwmember 20. The ring 19 is, in turn, fixedly secured to a horizontallyextending support rod 21 that extends through a sleeve 22 secured to theupper end of the bracket 15 and in which sleeve the rod is clamped by asuitable screw fastener 23. It will, of course, be understood that theillustrated mounting means for the dispenser 18 is merely illustrativeof a wide variety of such means which may be employed to fixedly securethe dispenser in a desired inclined relationship relative to the boxblanks 16 proceeding through the machine 10.

In order to maintain the hot glue at a desired temperature the dispenserhas a heated body. This may, for example, take the form of a cylindricalbody that is wound with an electrical heating coil 26, the wall of thebody being formed with a port 27 to which a suitable conduit means 28can be connected to provide fluid communication of the interior of thebody with a source of hot glue under pressure.

The rear end of the body 25 is closed by a plug 30, the two parts beingthreadedly interconnected as indicated at 31. The plug 30 is formed witha slightly enlarged head 32 having wrench flats by means of which theplug can be adjusted axially relative to the body 25, as a means ofadjusting the rate of flow of the hot pressurized fluid out of thedispenser. In order to provide a fluid seal, the inner end of the plug30 is formed with a circumferential groove 33 providing a pocket for anO-ring 34 that is in fluid-sealing engagement with the interior of thebody 25.

The forward end of the body 25 mounts an actuator retainer 35, the twoparts being threadedly innerconnected as indicated at 36. The forward,outer end of the retainer 35 has a slightly enlarged head 37 that isalso formed with wrench flats, whereby the retainer 35 can be adjustedaxially relative to the body 25. In order to provide a fluid sealbetween the two parts, the rear inner end of the retainer 35 is formedwith a circumferentially extending groove 38 providing a pocket for anO-ring seal 39.

The retainer 35, at its inner end, is externally formed with an annularshoulder 40 and, as is best seen in FIG. 4, a coaxially aligned pair ofpivot pins 41 are affixed thereto to protrude from the radial surface ofthe shoulder. The pivot means may take a variety of forms but,preferably, the radial surface of the shoulder 40 is formed withsemi-circular notches of a radius to matingly receive the short,cylindrical cross section pivot pins 41 and of a depth to leavesemicylindrical sections of the pins exposed, after the pins have beensoldered or otherwise affixed in place on the retainer 35. The pair ofpins 41 rockably support a wear ring 42 which in turn acts as a seat fora radially outwardly extending flange 43 that is integrally formed onthe rear end of a tubular actuator barrel 44. As is indicated in thedrawing, in FIGS. 2 and 3, the external diameters of the wear ring andflange 43 are sufficiently smaller than the internal diameter of thebody 25 to provide clearance for the rocking action of these twoelements about the pivot axis defined by the pivot pins 41. For the samereason the inner diameter of the wear ring 42 is larger than the axiallyextending cylindrical surface of the shoulder 40.

The actuator barrel 44 extends through a tapered passage 45 formedaxially through the retainer 35. Adjacent the smaller rear end of thepassage 45 the wall thereof is formed with an annular pocket 46 which,at its axially forward end, mounts back-up ring 47 on which an O-ring 48is seated. As is shown in FIG. 8, the retainer ring 47 is formed with aconcave rear face to matingly receive a portion of one side of theO-ring 48 and the inner edge 49 of the ring 47 is preferably formed witha taper that is a continuation of the taper of a retainer passage 45 andof a maximum diameter to provide a slight clearance to permit readydeflection of the actuator barrel 44. The O-ring 48 provides a fluidseal between the retainer 35 and the external surface of the actuatorbarrel 44 and the back-up ring 47, which is preferably made of arelatively hard material such as Teflon, prevents extrusion of theO-ring through the clearance between the external surface of theactuator barrel 44 and the surrounding wall portion of the passage 45.

When the dispenser 18 is mounted in operative position, as in FIG. 1,the axis defined by the pivot pins 4] should be disposed parallel to theplane in which the box blanks 16 travel and normal to the direction oftravel of the blanks. Accordingly, in oder to provide an externalindicator of the position of the pivot pins 41, the retainer 45, on itsforward end face, is provided with a diametrically opposite pair ofindicator grooves 50 that are parallel to the pivot pins 41. See FIG. I.

The lower end of the actuator barrel 44 is interiorly threaded toreceive the threaded shank of a nozzle 51. In order to provide a fluidseal between the nozzle 51 and barrel 44 the shank of the former isformed with a circumferential groove 52 to receive an O-ring seal 53.The nozzle is of hemispherical configuration at its lower end and isformed with an axially extending orifice 54 through which the hot liquidis exhausted.

Flow through the orifice 54 is controlled by a valve means that isoperable to open the flow passage upon deflection of the actuatorassembly by an article coming into contact with the nozzle 51. Thus, thenoxxle 51 is counterbored through the rear end thereof to define apassage 55 that is coaxially related to the orifice 54 and to form ashoulder on which an annular valve seat.

56 is mounted. An elongate valve stem 57 is formed with a reduceddiameter forward end that extends, with clearance, into the nozzlepassage 55 and terminates at its forward end in a valve head 58 that isadapted to close the valve opening of the seat 56 when the head 58 isseated thereon. As is indicated in FIG. 7, the side of the valve head 58is formed with a plurality of flats 59 to provide clearance for the flowof the fluid being dispensed therealong when the valve head 58 is in anopen position, as in FIG. 4.

In order to effect opening of the valve upon deflection of the actuatorassembly, the rear end of the valve stem 57 is operativelyinterconnected to a hollow spool 60 that is mounted within the body 25between the opposing end faces of the plug 30 and retainer 35. Thus, therear end of the valve stem 57 is externally threaded to mount a lock nut61 which bears against a concentric washer 62 that in turn bears againstthe inside of a forward end wall 63 of the spool 60. As is indicated inFIGS. 2 and 3, the outer diameter of the washer 62 is sufficientlysmaller than the internal diameter of the spool 60 to provide sufficientclearance to prevent binding between the parts upon actuation of thevalve. Similar clearances are provided between the inner edge of thewasher 62 and an inner edge of an opening 64 in the end wall 63 of thespool 60, relative to the valve stem 57. A spring means, e.g., apartially volute coil spring 65, is housed within the spool 60 havingits rear end biased against the plug 30 and its forward end biased onthe lock nut 61 to normally hold the spool against the rear end of theactuator assembly.

As is best seen in FIG. 5, the spool 60 is preferably made out of apiece of hexagonal bar stock which is machined to define a shallow,axially elongate cylindrical section 66 between opposite end hexagonalportions 67 and 68. The corners of the hexagonal portions 67 and 68 arefurther machined to round off the corners between adjacent flats on adiameter for mounting the spool 60 in a close, axially slideable fitwithin the body 25. Referring to FIGS. 2 and 3, there is thus defined anannular space between the spool 60 and the inner wall of the body 25 influid communication with the hot fluid port 27. Adjacent its forward endthe spool 60 is formed with a diametrically opposite pair of ports 70through the side wall of the spool and through the front end wall 63 toallow fluids to more freely enter the actuator barrel 44. As isindicated in FIGS. 2 and 3, the rear end face of the flange 43 of theactuator barrel is formed into a shallow frusto-conical surface 71providing a relief to ensure the free passage of the hot fluid into theactuator barrel.

With the just described configuration of spool 60 the area of mutualcontact between the spool 60 and the body 25 is minimized in order tominimize frictional resistance to axial reciprocation of the spool inthe body while, at the same time, the spool 60 is positively constrainedfor such axial reciprocation. As the high pressure fluid acts on both ofthe opposite sides of the actuator flange 43 the pressure of the fluiddoes not significantly inhibit deflection of the actuator barrel 44 inresponse to an object striking the nozzle 51. As contrasted to a balljoint, the pivot pins 41 provide a very low friction bearing fordeflection of the actuator barrel. At the same time, the coplanarrelationship of the median plane of the O-ring 48 and pivot axis of thepins 41, at the narrow neck of the retainer passage 45, minimizes theextent to which the O-ring must be radially compressed to accommodateangular deflection of the actuator barrel. With this combination offeatures, despite the presence of very high pressure fluid forces, thevalve mechanism is responsive to very light actuating pressures, wherebyopening and closing of the exhaust valve can be very preciselycontrolled.

As is shown in FIG. 2, when the dispenser valve is in the closedposition a slight clearance exists between the rear face of the spool 60and the forward face of the plug 30. The extent of this space can beadjusted as desired by adjusting the position of the plug 30 relative tothe body 25, by screwing the plug inwardly or outwardly to the desiredextent. With this arrangement, an external means is provided to adjustthe flow rate of the hot fluid out of the orifice 58 in the nozzle 51,corresponding to the degree to which the valve head 58 is allowed towithdraw from the valve seat 56.

As is indicated in FIG. 2, the dispenser 18 is adapted to be mounted atan angle of approximately 20 to the vertical with the nozzle 51protruding beneath the lowermost edge of the retainer head 37 tointercept the leading edge of a container blank 16 proceeding along theguide rails 14. As previously indicated, the dispenser 18 should be sooriented that the axis of the pivot pins 41 is parallel to the plane oftravel of the box blanks l6 and normal to the direction of travel.

Referring to FIG. 3, upon the leading edge of a container blank 16coming into contact with the nozzle 51 the actuator barrel is pivotedthrough a small are about the axis of the pivot pins 41. The actuatorflange 43 is thus moved through a corresponding arc and, as the spool isconstrained for purely axial translatory movement by the body 25, thespool is accordingly cammed rearwardly relative to the body. As a resultof this camming action the valve stem 57 is axially rearwardly withdrawnto the extent permitted by abutment of the rear end of the spool 60 withthe forward face of the plug 30 to deliver the hot liquid underpressure, at a desired rate, through the orifice 58 to be deposited ontothe container blank 16. As will be apparent, when the trailing edge ofthe blank 16 leaves contact with the nozzle 51 the parts are restored tothe closed position illustrated in FIG. 2 by the spring and the pistoneffect of the spool 60.

While a specific embodiment of the invention has been described andillustrated, it is intended to be purely illustrative and not limitativeof the invention.

What is claimed is:

1. In an automatic high pressure fluid dispenser the improvementcomprising:

a dispenser body having an interior chamber for containing a fluid underhigh pressure;

an actuator retainer affixed within said body and having a passage formounting an acutator therethrough;

an actuator having a tubular barrel extending through said passage ofsaid container with clearance therebetween;

pivot means, interconnecting a rear inner end of said retainer and arear inner end of said actuator, comprising rigid, opposed portions ofsaid retainer and said actuator that are biased into pivotal abutmentfor pivotal movement of said actuator relative to said retainer and bodyabout an axis that is normal to and intersects the longitudinal axis ofsaid passage of said retainer;

and an endless fluid seal means in said clearance intermediate saidpassage of said retainer and the exterior of said barrel, said sealmeans and said pivot axis being positioned in substantially a commonplane comprising the median plane of said seal means, the coplanarrelationship of said axis and said median plane of said seal means,minimizing radial compression of said seal means in response to pivotaldeflection of said actuator.

2. A dispenser as in claim 1 in which said passage of said retainer isformed with an annular pocket and said seal means comprsies an O-ring insaid pocket.

3. A dispenser as in claim 2 in which said pocket also mounts a back-upring for said O-ring at an axially forward end of said pocket, theaxially rearwardly facing surface of said ring being concave in radialcross section to define a complementary seat for said O-ring.

4. A dispenser as in claim 1 in which said pivot means comprises anexternal annular shoulder on said rear inner end of said retainermounting a diametrically opposite pair of bearings on which said rearinner end of said actuator pivots.

5. An actuator as in claim 4 in which said rear inner end of saidactuator is formed with a radially outwardly extending flange overlyingsaid shoulder of said retainer.

6. A dispenser as in claim 5 in which said bearings comprise a pair ofcoaxially aligned pivot pins secured to a radially extending surface ofsaid shoulder and rockably engaged by a ring that is interposed betweensaid flange of said actuator and said pins.

7. A dispenser as in claim 1 that is externally marked with indicatorsthat are parallel to said pivot axis.

8. An externally adjustable automatic fluid dispenser comprising:

a dispenser body having a port means for communicating the interior ofsaid body with a source of fluid under high pressure;

an actuator retainer affixed within said body and having a passage formounting an actuator therethrough;

an actuator having a rear inner end pivotally interconnected to a rearinner end of said retainer and having an actuator barrel extendingforwardly through said passage to protrude forwardly beyond forward endsof said retainer and of said body;

a nozzle mounted on the forward protruding end of said barrel and formedwith an outlet orifice therethrough;

an elongate valve member extending coaxially within said barrel andhaving a valve head at its forward end for normally closing a valve seataround said orifice;

a spool mounted in the interior of said body for slidable axialreciprocation and having a forward end coupled to a rear end of saidvalve member for withdrawing said valve head from said valve seat uponaxially rearward movement of said spool;

means intermediate said spool and said actuator for translating lateraldeflection of said barrel into axially rearward movement of said spoolto effect opening movement of said valve member;

and externally adjustable rigid means in said body to selectivelypositively limit the range of rearward axial movement of said spool tocorrespondingly limit opening movement of said valve member.

9. A dispenser as in claim 8 in which said last mentioned meanscomprises a plug that is threadedly engaged with said body to effectadjustment of said spool axially relative to said retainer.

10. A dispenser as in claim 9 in which said spool comprises a hollowmember that is normally biased forwardly against a flanged rear end ofsaid actuator by a means that also normally biases said valve memberaxially forwardly to a closed positon of said valve head on said valveseat.

11. An automatic fluid dispenser comprising:

a dispenser body;

a spool mounted in said body for slidable axial reciprocation betweenpositively fixed limits;

an actuator mounted in said body for pivotal movement about a singleaxis;

said actuator including a tubular barrel having a forward end thatprotrudes forwardly beyond a forward end of said body to terminate in anozzle that is laterally deflectable to effect pivotal movement of saidactuator barrel about said single axis;

means intermediate a forward end of said spool and a rear inner end ofsaid actuator to translate angular pivotal deflection of said barrelinto axial rearward movement of said spool;

and a valve means in said barrel that is operatively coupled to saidspool to effect opening and closing of said valve member in response toaxial movement of said spool between said fixed limits to control flowof fluids through an orifice in said nozzle.

12. A dispenser as in claim 11 in which said spool comprises a hollowmember that is normally biased forwardly against a flanged rear end ofsaid actuator by a means that also normally biases said valve means to aclosed position.

13. A dispenser as in claim 11 that includes an actuator retainer and anadjustable plug that are coaxially related to define said positivelyfixed limits for slidable axial reciprocation of said spool, said plugbeing externally adjustable to limit the range of rearward axialmovement of said spool to correspondingly limit opening movement of saidvalve means.

14. A dispenser as in claim 11 in which said valve means comprises anelongate valve member extending coaxially through said barrel and havinga valve head at its forward end for normally closing a valve seat aroundsaid orifice.

15. A dispenser as in claim 14 in which said means to translatedeflection of said barrel into rearward movement of said spool comprisesa diametrically opposite pair of pivot bearings on said actuator thatare rockably engaged by a radially outwardly extending flange on a rearinner end of said actuator.

16. A dispenser as in claim 11 in which said body has an actuatorretainer affixed thereto having a passage for mounting said actuator andin which an endless fluid seal means is disposed intermediate saidpassage of said retainer and the exterior of said actuator barrel, saidseal means and said pivot axis being positioned in substantially acommon plane.

17. A dispenser as in claim 16 in which said passage of said retainer isformed with an annular pocket and said seal means comprsies an O-ring insaid pocket;

said pocket also mounting a back-up ring for said O- ring at an axiallyforward end of said pocket, the axially rearwardly facing surface ofsaid back-up ring being concave in radial cross section to define acomplementary seat for said O-ring.

1. In an automatic high pressure fluid dispenser the improvementcomprising: a dispenser body having an interior chamber for containing afluid under high pressure; an actuator retainer affixed within said bodyand having a passage for mounting an acutator therethrough; an actuatorhaving a tubular barrel extending through said passage of said containerwith clearance therebetween; pivot means, interconnecting a rear innerend of said retainer and a rear inner end of said actuator, comprisingrigid, opposed portions of said retainer and said actuator that arebiased into pivotal abutment for pivotal movement of said actuatorrelative to said retainer and body about an axis that is normal to andintersects the longitudinal axis of said passage of said retainer; andan endless fluid seal means in said clearance intermediate said passageof said retainer and the exterior of said barrel, said seal means andsaid pivot axis being positioned in substantially a common planecomprising the median plane of said seal means, the coplanarrelationship of said axis and said median plane of said seal means,minimizing radial compression of said seal means in response to pivotaldeflection of said actuator.
 2. A dispenser as in claim 1 in which saidpassage of said retainer is formed with an annular pocket and said sealmeans comprsies an O-ring in said pocket.
 3. A dispenser as in claim 2in which said pocket also mounts a back-up ring for said O-ring at anaxially forward end of said pocket, the axially rearwardly facingsurface of said ring being concave in radial cross section to define acomplementary seat for said O-ring.
 4. A dispenser as in claim 1 inwhich said pivot means comprises an external annular shoulder on saidrear inner end of said retainer mounting a diametrically opposite pairof bearings on which said rear inner end of said actuator pivots.
 5. Anactuator as in claim 4 in which said rear inner end of said actuator isformed with a radially outwardly extending flange overlying saidshoulder of said retainer.
 6. A dispenser as in claim 5 in which saidbearings comprise a pair of coaxially aligned pivot pins secured to aradially extending surface of said shoulder and rockably engaged by aring that is interposed between said flange of said actuator and saidpins.
 7. A dispenser as in claim 1 that is externally marked withindicators that are parallel to said pivot axis.
 8. An externallyadjustable automatic fluid dispenser comprising: a dispenser body havinga port means for communicating the interior of said body with a sourceof fluid under high pressure; an actuator retainer affixed within saidbody and having a passage for mounting an actuator therethrough; anactuator having a rear inner end pivotally interconnected to a rearinner end of said retainer and having an actuator barrel extendingforwardly through said passage to protrude forwardly beyond forward endsof said retainer and of said body; a nozzle mounted on the forwardprotruding end of said barrel and formed with an outlet orificetherethrough; an elongate valve member extending coaxially within saidbarrel and having a valve head at its forward end for normally closing avalve seat around said orifice; a spool mounted in the interior of saidbody for slidable axial reciprocation and having a forward end coupledto a rear end of said valve member for withdrawing said valve head fromsaid valve seat upon axially rearward movement of said spool; meansintermediate said spool and said actuator for translating lateraldeflection of said barrel into axially rearward movement of said spoolto effect opening movement of said valve member; and externallyadjustable rigid means in said body to selectively positively limit therange of rearward axial movement of said spool to correspondingly limitoPening movement of said valve member.
 9. A dispenser as in claim 8 inwhich said last mentioned means comprises a plug that is threadedlyengaged with said body to effect adjustment of said spool axiallyrelative to said retainer.
 10. A dispenser as in claim 9 in which saidspool comprises a hollow member that is normally biased forwardlyagainst a flanged rear end of said actuator by a means that alsonormally biases said valve member axially forwardly to a closed positonof said valve head on said valve seat.
 11. An automatic fluid dispensercomprising: a dispenser body; a spool mounted in said body for slidableaxial reciprocation between positively fixed limits; an actuator mountedin said body for pivotal movement about a single axis; said actuatorincluding a tubular barrel having a forward end that protrudes forwardlybeyond a forward end of said body to terminate in a nozzle that islaterally deflectable to effect pivotal movement of said actuator barrelabout said single axis; means intermediate a forward end of said spooland a rear inner end of said actuator to translate angular pivotaldeflection of said barrel into axial rearward movement of said spool;and a valve means in said barrel that is operatively coupled to saidspool to effect opening and closing of said valve member in response toaxial movement of said spool between said fixed limits to control flowof fluids through an orifice in said nozzle.
 12. A dispenser as in claim11 in which said spool comprises a hollow member that is normally biasedforwardly against a flanged rear end of said actuator by a means thatalso normally biases said valve means to a closed position.
 13. Adispenser as in claim 11 that includes an actuator retainer and anadjustable plug that are coaxially related to define said positivelyfixed limits for slidable axial reciprocation of said spool, said plugbeing externally adjustable to limit the range of rearward axialmovement of said spool to correspondingly limit opening movement of saidvalve means.
 14. A dispenser as in claim 11 in which said valve meanscomprises an elongate valve member extending coaxially through saidbarrel and having a valve head at its forward end for normally closing avalve seat around said orifice.
 15. A dispenser as in claim 14 in whichsaid means to translate deflection of said barrel into rearward movementof said spool comprises a diametrically opposite pair of pivot bearingson said actuator that are rockably engaged by a radially outwardlyextending flange on a rear inner end of said actuator.
 16. A dispenseras in claim 11 in which said body has an actuator retainer affixedthereto having a passage for mounting said actuator and in which anendless fluid seal means is disposed intermediate said passage of saidretainer and the exterior of said actuator barrel, said seal means andsaid pivot axis being positioned in substantially a common plane.
 17. Adispenser as in claim 16 in which said passage of said retainer isformed with an annular pocket and said seal means comprsies an O-ring insaid pocket; said pocket also mounting a back-up ring for said O-ring atan axially forward end of said pocket, the axially rearwardly facingsurface of said back-up ring being concave in radial cross section todefine a complementary seat for said O-ring.